Although I was really looking for design paramameter for rapid prototyping, those snap-fit design links, which were for finished products, are certainly useful ideas. They give both examples of types of snaps, as well as great engineering information about designing them.

But, I dont know how much the those design guidelines apply to rapid prototyping. We have to deal with materials that are stronger in some directions than others, and have other issues that are not present in injected molded parts. Still, we are often making rapid prototypes for items that will later be injected molded. When we prepare a model for the rapid prototyping, we often make changes to the model to accommodate the limitations of the machines.

-Joe